Current Research

Thursday, October 28, 2010

With the announcement of the newly discovered Rhinopithecus strykeri yesterday, we were only given a glimpse of this new species through an illustration and a computer modified image (Photoshopped none the less). I bet everyone was wondering why aren't there any pictures of these snub-nosed monkeys.

Ponder no more. Here's a photo from National Geographic showing local hunters with a dead R. strykeri that's about to be dinner(photo by Ngwe Lwin). The researchers (Geissmann et al., 2010) were not able to procure a photo of any live R. strykeri. Supposedly, they captured some wild ones but they had escaped before pictures were taken. R. strykeri are threatened by hunting and habitat destruction due to logging.

Wednesday, October 27, 2010

As if fate is testing me, I just had a Facebook conversation yesterday about new species "discoveries" and how ethnocentric they are. I mean, really ... do you really think that until these new species are "discovered" by scientists, no one (even people that lives in the area) knew of these animals? Probably not. Using the word "discovered" to formally acknowledge a species seems antediluvian.

While there are currently no images of living specimens of this new species available Fauna & Flora International has commissioned an artists impression of the new species in its habitat, based on field sightings and a carcass of the newly discovered species. Image from Martin Aveling/Fauna & Flora International.

Anyway, a team of primatologists supposed discovered a new species of snub-nosed monkey in Northern Myanmar during their Hoolock Gibbon Status Review early this year. The new species was formally named Rhinopithecus strykeri, after the President and Founder of the Arcus Foundation Jon Stryker. The locals do have a name for these snub-nosed monkeys. They call them "mey nwoah" or "monkey with an upturned face".

This primate reported has an upturned nose which, according to the locals, made them sneeze when it rains. Locals observed that to avoid getting rain water into their nose, R. strykeri would sit with their heads tucked in between their legs. Their pelage is entirely black except for a white tuft on their ears, chin beard and the perineal end. It has a relatively long tail, about 140% of its body. R. strykeri is the first species of the Rhinopithecus genus to be found in Myanmar. The other four species (R. roxellana, R. bieti, R. brelichi and R. avunculus) are found in China and Vietnam. R. strykeri's range is limited only to the Maw River area. There are estimated about 260 to 330 individuals of R. strykeri left in the wild, making them Critically Endangered according to IUCN.

Tuesday, October 19, 2010

EDIT: Recent studies by Dr. Anna Nekaris and her team have shown that slow lorises are both poisonous AND venomous (how interesting!). It has came to my attention that this blog post is being used by those to argue for the suitability of slow lorises as pets. I concluded that slow lorises are not poisonous, but could be venomous, citing lack of evidence. However, this has since been proven incorrect with evidence to support that slow lorises are BOTH poisonous and venomous.Just to make one thing very clear, I do not condone keeping nonhuman primates as pets.I passionately plea that you do not purchase or keep slow lorises as pets. Slow lorises do not make good pets and the pet trade that brought these lorises to you are cruel and unsustainable. Please read this post on why we need to not support slow loris pet trade.- Prancing Papio

I must say, the idea of venomous primates never crossed my mind. While venomous species do exist in mammals, it is much more common in insects, reptiles and fishes. In primates, slow lorises (genus Nycticebus) are thought to be venomous in Thai folklore (Wilde, 1972) but are they really?

NycticebusAs of 2010, the genus Nycticebusconsists of four species: Pygmy slow loris (Nycticebus pygmaeus), Javan slow loris (Nycticebus javanicus), Sunda slow loris (Nycticebus coucang) and Bengal slow loris (Nycticebus bengalensis). The Javan slow loris was previously recognized as a subspecies but has since been elevated to species status. These prosimians are found in different parts of Southeast Asia. Nycticebus range, in red. Illustration from Primate Info Net.

Colors and markings in Nycticebus species and subspecies. Illustration from Loris Conservation.

Venomous vs. Poisonous

Although the words "venomous" and "poisonous" are used interchangeably in everyday speech, they are actually fundamentally different. By definition, venom has to be injected into the body, introduced by a bite or a sting. Poison, on the other hand, is ingested or inhaled into the body by the victim. Thus, venomous and poisonous animals are altogether different.

The blue dart frog (Dendrobates azureus) is a poisonous animal while the Indian cobra (Naja naja) is a venomous animal.

Brachial gland of slow lorises

The flexor surface or the ventral side of the elbow has a slightly raised but barely visible swelling termed the brachial gland (Hagey et al., 2006; Krane et al., 2003). Observations from captive slow lorises show that when the animal is disturbed during handling, they secrete about 10 microliters (μL) of clear, strong-smelling fluid in the form of an apocrine sweat (exudate) from their brachial gland . Usually, male and female slow lorises assume a defensive stance when disturbed. They bend their heads downwards between uplifted forelegs, rubbing the brachial gland exudate onto their head and neck. Slow lorises frequently lick their own brachial gland regions and also wipe their brachial gland against their head. The brachial gland is active in lorises as young as 6 weeks old (Hagey et al., 2006). Illustration shows the brachial gland (dark patch) on the ventral side of a slow loris. Drawing by Helga Schulze (Krane et al., 2003).

Brachial gland exudate and Fel d 1

The brachial gland produces exudate with an allergen that is similar to the Fel d 1 cat allergen (Hagey et al., 2006; Krane et al., 2003). This brachial gland exudate shares a high degree of similarity in sequence, as well as unusual disulfide-bridged heterodimeric structure similar with Fel d 1. Fel d 1 is an allergen found mostly in saliva and the sebaceous glands (glands found inside the skin) of domestic cats, Felis catus. Humans with a cat allergy are allergic to five known allergen produced by domestic cats, Fel d 1 being one of them. However, the biological function of Fel d 1 is still currently unknown (Grönlund et al., 2010).

So are slow lorises venomous or poisonous?
To answer this, let's revisit the definitions of venomous and poisonous. A venomous animal injects toxins into its victim's body by bite or sting. A poisonous animal, on the other hand, produces toxins that are poisonous once inhaled or ingested. Medical literature shows that human - slow loris injuries come from slow loris bites and not from ingesting their toxins. So are slow lorises venomous? Well, not quite.

Slow lorises have needle-like teeth called dental combs or tooth combs on their lower jaw. Paired with the constant licking of the brachial gland, it is not surprising that one would assume the dental comb plays a part in injecting brachial gland exudate into unsuspecting victims (Hagey et al., 2006). However, this is not the case.

Used for grooming, dental combs might look menacing to some but their function is less sinister than one might conjure up. A bite from a slow loris is painful due to their sharp pointed teeth. Illustration of slow loris teeth from Loris Conservation. The dental comb is on the lower jaw, shape like a spade.

Wilde (1972) reports that the victim of a slow loris bite immediately succumbs to anaphylactic shock (extreme allergic reaction) followed by hematuria. In spite of that, the victim fully recovered. There is no clinical evidence of toxic substances in slow loris saliva to support the notion that they are venomous (Wilde, 1972).

Another incident involves a 34 year-old woman who is 19 weeks pregnant. She was bitten by a pygmy slow loris at the zoo she works in. The patient only complained about an acute pain at the location where she was bitten. She did not go into anaphylactic shock (Kalimullah et al., 2008).

Reports of slow loris bites are rare in literature. However, based on these published reports, it seems that slow loris bites are not venomous (Kalimullah et al., 2008; Wilde, 1972). Due to the high degree of similarity between the brachial gland exudate of slow lorises and the Fel d 1 allergen in domestic cats, the anaphylactic shock expressed by victims is probably just a reaction to the exudate's allergen.

What is the function of the brachial gland exudate?

Hagey et al. (2007) posit that the brachial gland exudate is used as olfactory signalling to broadcast individual home range and territories. Most nocturnal primates rely on olfaction -- slow loris included. Since brachial gland exudates are not an immediate response to stress or pursuit, their function might be to deter predators, warn other slow lorises of danger or even both (Hagey et al., 2006).

I'm looking forward to more studies on these prosimians and the properties of their brachial gland exudates. More research, as well as slow loris bite records, are needed to elucidate the effects of brachial gland exudates on humans.

Interspecies grooming is not unheard of and does occur naturally. While grooming can be dyadic and triadic (or even more), it can also be one-directional. Since grooming is central to primate sociality, there are reported instances of grooming between two different species of primates or even between a primate and non-primate. Grooming has many functions: hygiene, social bonding and even gaining favor.

I found this video yesterday (above) on Youtube by thekingchivas. I could not believe my eyes with what the camera caught. It shows a Malayan tapir (Tapirus indicus) being groomed by a White-cheeked gibbon (Nomascus leucogenys). After doing a Google search, I realize that this is not an isolated incident. Apparently The Bronx Zoo is also aware of this behavior and had posted its own video, which seems to be a separate incident from the one caught by thekingchivas.

I'm not going to definitively say that the tapir will not reciprocate in this grooming but chances are highly unlikely. I wonder what makes these gibbons (there were two females in the exhibit, The Bronx Zoo currently has a mated pair) groom their fellow exhibit-mate. While this might not be an altruistic exchange, we can view it as a mutual symbiotic relationship. Neither animal had its fitness reduced, so it is not altruism. Instead, both individuals benefit from this interaction so it is symbiotic.

The gibbons meticulously groom the tapir to remove insects, which in turns become a tasty snack for these gibbons. The tapir on the other hand, benefits by having pesky insects removed off its body. Is it significant that both animals are female? Is this behavior natural? There are recorded accounts of interspecies grooming between primates and non-primates, so it is quite likely.

A macaque grooming a goat on the streets of Chilkur, India. An example of mutual symbiosis between a primate and a non-primate. Photo by Libran Lover from A Lover's Journal.

A langur grooming a pig in Jaipur, India. Somehow nature managed to put two animals that I have polar opposite feelings together (one I love, the other I hate). Another example of mutual symbiosis between a primate and a non-primate. Photo by Christa Kate Hyland from Laddus and Langis.

The range of both Malayan tapirs and White-cheeked gibbons does not overlap. Malayan tapirs occur in Malaysia, Indonesia, Thailand and Myanmar while White-cheeked gibbons are found in Vietnam, Laos and the Yunnan province of China. Therefore, interspecies grooming between Malayan tapir and White-cheeked gibbon is probably a novel behavior that cannot be observed in the wild.

Map shows the current and historic range of Malayan tapir, as of 2003. Notice that Malayan tapirs do not occur in Vietnam, Laos nor China (Yunnan province) where White-cheek gibbons occur. Illustration by Sasha Kopf from Wikipedia.

Wednesday, October 13, 2010

The Four Stone Hearth is back for yet another exciting edition. Before we begin, I would like to thank Afarensis once more for taking on the ownership of Four Stone Hearth. Thanks for keeping the blog carnival momentum going. I'm happy to host Four Stone Hearth for the third time. It gets better every time I host it! Thanks to those that submitted their entries early, you totally made my life easier.

Our first submission comes from Somatosphere, whose blog post is a book review about Claude Levi-Strauss (1908 - 2009). In the post, Leo reviewed the book "Claude Levi-Strauss: The Poet in the Laboratory", an autobiography by author Patrick Wilcken. This is the first English-language biography of Levi-Strauss, the French anthropologist and ethnologist who's sometimes referred to as the "father of modern anthropology".

Bonn submitted an interesting post on the anthropology of animal superstition in his blog, Time Travelling. I must say that after reading his post, it reminded me of my own childhood in Malaysia where animal myths are the central theme for disasters and good luck. Read Bonvito's post, "Animal Lores: Myths, Disasters, and Animals".

Before I end this edition of Four Stone Hearth, I'd like to share a video with you of Betty White (the last surviving Golden Girls) as an Anthropology professor on the NBC sitcom "Community". Those that know me knows I love Betty White but her playing an Anthropologist is this gay boy's dream come true! White plays Prof. Bauer and the clip below is her explaining the movie "Inception" to two indigenous men. Be aware that she is dropping spoiler bombs (which is why she is speaking English instead of the tribe's language).

Thank you everyone for contributing to this edition of Four Stone Hearth. The next edition of Four Stone Heart will be hosted over at Sorting Out Science on October 27th. Please send your submissions to Sam or Afarensis.

Thursday, October 7, 2010

The Prancing Papio will be hosting the next edition of Four Stone Hearth next Wednesday (October 13th, 2010). The Four Stone Hearth focus on four subfields: archaeology, socio-cultural anthropology, bio-physical anthropology and linguistic anthropology.

The Four Stone Hearth is a blog carnival that specializes in anthropology in the widest (American) sense of that word. Here, anthropology is the study of humankind, throughout all times and places, focussing primarily on four lines of research:

Archaeology

Socio-cultural anthropology

Bio-physical anthropology

Linguistic anthropology

Each one of these subfields is a stone in our hearth. Four Stone Hearth is published bi-weekly, Wednesdays in odd-number weeks.

If you would like to submit content to the next issue of the carnival, please write to the keeper of the blog in question or to Afarensis. You are encouraged to submit other bloggers' work as well as your own. If you would like to host the carnival, please write to Afarensis. Please email me on PrancingPapio at gmail dot com for entries.

Friday, October 1, 2010

An insightful paper published by Ross et al. (2010), compares zoo-living ape behavior inside their holding and exhibit areas in Lincoln Park Zoo, an accredited member of Association for Zoos and Aquarium (AZA). Zoo animals usually have at least two areas where they are housed (excluding some aquatic animals): the holding area and the exhibit area. During visiting hours and at night, zoo animals are housed in their exhibit area. In the morning, before the zoo opens, they move into the holding area to receive husbandry care and their morning food ration.

One of the chimpanzee from the study, Kipper (now deceased), from Lincoln Park Zoo interacting with a child. Photo by Chicago Tribute.

Holding and exhibit areas differ in size, design and functionality. A study by Ross and Lukas on 11 AZA-accredited zoos shows that holding areas are usually about 40 times smaller than exhibit areas (Ross et al., 2010). At the Lincoln Park Zoo, the holding area is about 9.3% of the size of the exhibit area (for both gorillas and chimpanzees). Whereas the exhibit area is designed for the complexity and to mimic the natural environment of its animal inhabitant, the holding area is usually designed for simplicity and functionality to meet husbandry needs.

Seven gorillas (2 males, 5 females; N = 7) and seven chimpanzees (3 males, 4 females; N = 7) were observed in this study. I should point out that the authors of the study is by no means criticizing Lincoln Park Zoo. It is an informal observation of behavioral changes for these animals in different environment. The result of the study shows that:

GorillasInside the holding area - Increased locomotion and affiliative behavior. Also showed increased rates of aggression, self-directed behavior (subject touches, manipulates or examines the body, skin, or hair) and solitary play. Were in close proximity with each other.

Inside the exhibit area - Increased feeding and foraging behavior and also sexual behavior.

ChimpanzeesInside the holding area - Increased aggression. Increased rate of scratching and self directed behavior (subject touches, manipulates or examines the body, skin, or hair). Were in close proximity with each other.

Inside the exhibit area - Increased feeding and foraging behavior.

Schematic representation of a typical holding area suite for an individual chimpanzee or gorilla social group at the Regenstein Center for African Apes. Shaded areas indicate animal enclosures; noncolored areas are sections of human activity (caretakers and data collectors). (Ross et al., 2010)

Both gorillas and chimpanzees showed increased aggression accompanied with self directed behavior when inside holding area. Increase in aggression can sometimes be attributed to overcrowding and self directed behavior generally means that an animal is nervous. Being constrained in a smaller space increases the chance of mixed-sex and mixed-dominance encounters thus resulting in agonistic and submissive observations. When inside exhibit areas, both apes exhibited an increase in feeding and foraging behavior. This presumably is due to their feeding and foraging habit in the exhibit area. If I remember correctly, one of the major breakthrough in exhibiting apes (and most animals) is to encourage foraging behavior throughout the day. It is no surprise that these apes exhibit these behaviors.

Chimpanzee subjects in a single enclosure in a holding area suite, during a period of free access (following training and research protocols). Photograph was taken from the central caretaker area. (Ross et al., 2010)

These apes reacted differently when inside their holding area than in their exhibit area because they are exposed to different sensory. Apart from the difference in size and complexity, these two areas also differ in the degree of human interaction, cross-species presence, environmental factors and time spent between these two areas. An understanding of these differences and motivational factors is important in promoting optimized environments for captive apes. The authors encourage that zoos would consider species-specific functional, physical and social preferences when designing enclosures for apes regardless of frequency of use.